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Can someone please tell me how to do this i really need the method

Sodium carbonate exists in hydrated form, Na2CO3.xH2O, in the solid state. 3.5 g of a sodium carbonate sample was dissolved in water and the volume made up to 250 cm3. 25.0 cm3 of this solution was titrated against 0.1 moldm-3 HCl and 24.5 cm3 of the acid were required. Calculate the value of x given the equation: Na2CO3 + 2HCl  2NaCl + CO2 + H2O

Reply 1

GreenCub

Here's a start:

Use the titration information to calculate the number of moles of carbonate that reacted first - then calculate the corresponding mass of sodium carbonate and see what the difference is between that and 3.5g - that difference is accounted for by the water.